Bottle Opener

For our first project, Sarah and I  had to design a two dimensional bottle opener. The bottle opener had to be capable of opening a non-twist-off soda bottle, be made from a single piece of Delrin plastic, and could not be bigger than 6'' in any dimension. To start the project, Sarah and I went through a brainstorming session. Many ideas came out of the session.

Brainstorming Session

From all of the ideas, we thought ten of them were the most feasible and we drew better mock ups of them. We organized them by variations on different shapes.

The Ledge Designs

The Inverted Circle Designs

Circular Designs

The first idea was the ledge design. We thought it could open the bottle by providing a lever for the bottle to be opened on with the smaller end under the bottle and the larger end on top. We thought the teeth in the last one could grip on the bottle better (and that it looked like a shark). Ultimately,  we didn't choose this design because we thought it would be easy for the side to get dull and not open the bottle.

Our second idea was the inverted circle. We thought the teeth could have helped grip the bottle or the shaped handle would make the opener more comfortable for the user. Ultimately, we did not choose this design because we thought it would need more force than possible to open the bottle.

Our third idea was the circular designs. We thought that since the opener was more compact, it could provide more force to open the bottle than our other ideas. We did not choose the donut or the oval because we thought that the measurements would need to be precise in order to work, which doesn't always work with a laser cutter. We thought the half-circles could open the bottle by having the straight edge on the underside of the bottle cap and the rounded edge on top of the bottle cap, providing the right leverage and force to open the bottle. We went with the circular half-circle because we thought the design was more fun than the hand shaped one.

Our next step was cutting the piece out of foam core.

Doesn't it look happy?

Our outside circle ended up having a 30mm radius with the middle half circle having a  20mm radius.

Then we needed to make the piece in solidworks. Neither Sarah or I had worked in solidworks before but we soon got used to it. Our piece looked like..

Solidworks piece of the foam core.

The final step was to send the piece to the laser cutter to print it out. There was some trouble finding the right file to make it print. When we got it to work, we printed the piece on 3/16'' delrin because we thought it would be thick enough to be stable, but thin enough to fit under the bottle cap. The final product came out.

Final Delrin Piece!

Engineering Analysis

Cantilever Beam Equation: 

delta=deflection

F=Force

L=Length

E=Young's Modulus (material stiffness)

                          I=Area moment of inertia (stiffness of cross-sectional area)

For this project, we had to use delrin as the material of our object so the Young's Modulus could not be influenced by the design of our bottle opener. It is also hard to tell the Force someone will put on the bottle opener so that could also not be influenced by the design of our opener. Our model was influenced by the Length (from the top of our head to the top of our mouth) and the area moment of inertia. We chose this design as opposed to one with a handle because the length from where the force is applied to were it opens the bottle was the shortest. We also made it a circle because we concluded that the area moment of inertia would be the largest. Therefore deflection would be small and it would be able to open the bottle cap.

Summary

1) Brainstorming-Create many different ideas

2) Top Ten Ideas- Look at all the ideas and pick the 10 most feasible ideas

3) Chose Best Idea to try- Circle because deflection would be small, would provide best leverage, and looked the best.

4) Cut piece out of foam core

5) Make piece in Solidworks

6) Laser Cut the Bottle Opener

7) Open the Bottle!- Our bottle opener worked the second time we tried it in class. When we were using the bottle opener before the presentation, we noticed that it would sometimes fail because the flat part could not get fully under the bottle.

If I had more time, I would experiment with sanding the flat part of the bottle opener down so that 

more of the part could get underneath the bottle cap. I would also try different sized half-circles in the middle of the design to see if it would change how easily the bottle cap would come off. If I had a lot more time, I would also want to experiment with different types of bottle openers to see which one works the best.